


Mixing timelines

by Bookworm1890



Category: Undertale (Video Game)
Genre: F/F, F/M
Language: English
Status: In-Progress
Published: 2019-04-25
Updated: 2019-06-09
Packaged: 2020-01-31 20:31:36
Rating: General Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 6
Words: 1,951
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/18598876
Author URL: https://archiveofourown.org/users/Bookworm1890/pseuds/Bookworm1890
Summary: What would happen if timelines mixed? If under fell and underswap became one?(Like blue and fell sans met)





	1. Chapter 1

**Author's Note:**

> Hi...this is my first story so please be nice.  
> If you see any spelling mistakes please tell me. Thank you for reading this!  
> Enjoy!

"Kid? Where are you?"  
Sans walked through the forest looking for frisk. She had gone missing again and Toriel was worried sick. Sans had offered to find them.

He thought back to the last time Frisk had gone missing. She had been depressed and was going to reset. Sans had talked her out of it and brought her home.

Frisk hadn't been like that for a while, so Sans didn't understand what had made her disappear.

A bush rustled and Sans stopped.  
"Kid? You there?"  
Sans stepped towards the bush. There was a golden flower glaring up at Sans.

"Oh, look who it is, the smiley trashbag" Flowey sneered. "What do you want..."  
"I'm looking for Frisk. Have you seen her?" Sans ignored Floweys insult.  
_Stupid weed..._ Sans thought.  
Flowey rolled his eyes.  
"You lost her again? Wow"

Flowey disappeared into the ground and reappeared a few meters away.  
"She went this way"  
Sans followed Flowey. Soon he began to recognize where they were.  
"Hey, this is the path to Mt Ebbot, right?"  
"So...the trash knows geography" Flowey said. "Yes. I don't know why she climbed the mountain again"

Sans frowned. He turned a corner and saw Frisk. She was on the ground, curled up in a ball.  
"Kid!"  
"Frisk!"  
Sans and flowey both cried out at the same time.  
Flowey got to her first, because he could go underground. Sans dropped to his knees next to the human.

"Frisk?" Sans could see her soul so he knew she was still okay.  
Frisk stirred at her name. She yawned and saw Sans.  
She signed - _Sans? What you doing here?_ -  
"Looking for you kid. Come on. Let's go home" he picked up Frisk and started walking home, Flowey following them


	2. Pie and Puns

**Summary for the Chapter:**

> Sans brings Frisk back and Tori makes pie

Toriel put the pie into the oven and turned to Papyrus. He was making spaghetti again and she had to stop him from splattering it all over the walls in her kitchen.

"Papyrus, dear, don't put the heat that high!" Toriel rushed over to stop him from starting a fire.  
"OH, I'M SORRY, YOUR MAJESTY!"   
"Its OK. Why don't you go and find Undyne? She would like some spaghetti, I'm sure" Toriel needed some time to herself.   
"THAT IS A GREAT IDEA! I'll GO FIND HER NOW!" Papyrus went to run out of the door but he forgot to open it first.   
"OW. REMEMBER PAPY, USE THE HANDLE! NYEH HEH HEH..." He left once he had opened the door.

Toriel sat down at the table and started crying. Why had frisk ran off? Was she OK? Had Toriel done something wrong?

Toriel heard the front door open and quickly dried her tears. Was Papyrus back already?

"Tori? I found her"

Sans

Toriel rushed through and took frisk from Sans. Frisk stirred slightly, but stayed asleep.  
"Oh, my child... Where was she?"  
Sans flopped down onto the sofa. "She was near the mountain"  
"The mountain? Oh child..."  
Toriel carried Frisk through to her room and gently put her to bed.  
"Sweet dreems, my child"

Toriel went back through and sat next to sans.  
"Oh, yeah, Flowey led me to Frisk" Sans told Toriel.  
"The flower? I wonder why..." Toriel jumped as intense bleeping noise came from the kitchen.  
"The pie!"

Once Toriel had saved the pie, and the kitchen, she brought two plates through to the living room.  
"Here you go" she hands a plate to Sans.   
"Thanks Tori" Sans perks up at Toriels pie. "Your cooking is always SANsational"

Toriel laughs and kisses him on the four head. Sans blushes and looks embarrassed.  
"Ha ha ha! You look like you've had a bad time!"

Sans gaze darkens for a second, then gone the next. Toriel frowned slightly.  
"Are you okay Sans?" She asked.  
"I'm... Fine. Don't worry about me" he smiles at her. "After all, you need to give Pappy a tuTORIEL on cooking"

Sans and Tori both laugh at the awful pun.  
"It sounds like you needed to go all the way down to the bone to think of that one!"

They go back and forth like that, almost crying with laughter till the door opens.  
"SANS? WHY ARE YOU CRYING?!"

**Notes for the Chapter:**

> If you would like any aus added please comment below


	3. Frisk

**Summary for the Chapter:**

> Frisk wakes up

"SANS? WHY ARE YOU CRYING?"

The loud voice of Papyrus woke Frisk up. She opened her eyes and looked around her room. She frowned. How had she gotten here?

💧✌☠💧

Oh yeah... Sans had come looking for her. Frisk could here him now, but not his words, just his low voice that could send shivers down her spine.

👍⚐💣☜ ❄⚐ 💣☜

Frisk went out into the corridor. Undyne looked round and saw her. "Hey punk" Frisk smiled and waved. She had always liked Undyne, even when she'd... *no...don't think about that...*

Toriel saw her and smiled. "Frisk, would you like some pie or spaghetti?" She thought for a second and signed

-would I be allowed both?-

"OF COURSE HUMAN FRISK!" Papyrus headed through to the kitchen with Undyne. "WE NEED TO COOK IT FIRST THOUGH" Toriel rushed after them.

"Please don't burn down my kitchen!"

Sans looked over at Frisk. "Looks like its just us now, heh..." Frisk went and sat down next to him.

-I'm sorry-

"Its ok. I'll catch up on my sleep...if Papy doesn't poison us with his spaghetti..."

☟☜ 🕈⚐☠🕯❄

Frisk smiled. -he won't- she signed.

"So...wanna tell me why you ran off?" She glanced down. "Frisk? You know you can tell me anything, right?"

Frisk hesitated, then signed -I've been hearing...-

**Notes for the Chapter:**

> OK. I've written ahead in the story so if you wanna see some more AUs, ur gonna have to wait. Sorry.  
> Also sorry for long break between this chapter and the last. I had something I had to do.


	4. Sleep and Spaghetti

**Summary for the Chapter:**

> Spaghetti.

"THE SPAGHETTI IS READY!"

Papyrus and Undyne brought 5 plates of pasta through. "Careful! Undyne, do you really have to carry 4 plates?!" Toriel looked worried that someone would drop a plate.

Frisk took her plate and had a bite. She perked up. -its delicious!-

"Yeah, pap, it's SANsational"

"SANS! NO PUNS WHILE EATING!!"

Undyne slapped Papyrus on the back. "Its great! You've gotten way better at cooking!"

"Its because of Tori's tuTORIELS" Sans said,"  PASTA lot of other peoples sapg bol if you ask me!"

Papyrus groaned at his brothers terrible pun. Once everyone had finished their spaghetti Toriel got 3 plates of her butterscotch-cinnamon pie.

"Sans? Would you like another piece?" Sans was asleep. Frisk giggled and got a black marker pen.

"WHAT ARE YOU DOING FRISK?" She held a finger up to her lips. Pappy was loud and she didn't want Sans to wake up.

She drew hearts and stars on his skull.

Undyne was trying not to laugh and Toriel was smiling.

-no one tell him- Frisk signed -let him find out himself-

"HMM.. I HOPE IT'LL WASH OFF..." Papyrus said.

"What'll wash off...?" Sans mumbled. He was still half asleep. Frisk jumped and dropped the pen on her jumper.

"The pen on Frisk's jumper" Toriel said, with a warning glance to Pappy.

"Pen will wash off... Don't worry..." Sans fell asleep again.


	5. Messages and code

**Summary for the Chapter:**

> Alphys has something to show Sans

Sans slept for the whole night. In the morning he went through to the bathroom. He kept a change of clothes at Tori's cause he'd fallen asleep multiple times. He looked in the mirror.

...

Frisk

He went back through. Toriel was up. "Tori...why didn't you stop Frisk? Or at least tell me..." Toriel smiled.

"You where fast asleep and Frisk would've done it even if I told her not to. Anyway, Alphys called. She wants you to go by the lab today. Something about strange readings"

"Ok, welp, I'm going to was this pen off. See ya"

Sans washed off the pen marks, but he was impressed by Frisks drawing skills. Once he was done he took a 'shortcut' to Alphys lab.

"Hey, Doc" Alphys jumped and dropped her tablet. Sans caught it with blue magic. "You wanna be more careful, alp, never know when it'll break"

"S-sans...that was y-your fault!" Alphys stuttered as she took the tablet back. "Heh, anyway, Tori said you called"

"Y-yes... Um... Right. You know Mettaton, w-well he... He seems to h-have a feature I didn't m-make" Alphys leads Sans upstairs to where Mettaton is being rebuilt. Mettaton's head and torso lay on the table together. His arms and legs where scattered about the room.

"So, Doc, you redesigning Mettaton then? That's pretty hard to process!" Alphys stared at Sans. She did a sort of sigh laugh stutter thing and said

"K-kinda... He wanted some new f-features..."

"Huh" Sans wandered over to the table. "So... What's the feature?"

"Um... Some sort of m-message receiver, or something like that" Sans's eye sockets widened with surprise.

"Wait... You got a message through your entertainment robot. What was the message?!" Alphys handed Sans a piece of paper. On it where some marks:

💧✌☠💧

👍⚐💣☜ ❄⚐ 💣☜

☟☜ 🕈⚐☠🕯❄

"Huh, I wonder what it means..." Sans looked at the note. The marks looked...familiar. "Bet you regret that. ReMORSE code!"

"R-really?! Anyway...I-I've put it through every d-decoding machine I could t-think of!"

Alphys turns to Mettaton's body and picks up a screwdriver. "I-i got nothing. Not e-even what code or language i-it's in!"

Sans frowned. He felt like he knew the code. "I'll look in the librarby with the kid for it. Can I get a copy?"

"S-sure!" Alphys takes the sheet over to the printer and copy's it. "Here y-you go" she hands him the sheet. "Thanks Doc" Sans goes through the nearest doorway and heads back to Tori's.

**Notes for the Chapter:**

> OK. I'm in the middle of writing chapter 7, and I'm adding dancetale and outertale. This is gonna be fun. Also, if you want any other AU's added, comment them and I'll add them. But please no horror AU's. Please


	6. Knock On The Door

**Summary for the Chapter:**

> Sans goes back to Tori's and there is an unexpected visitor

**Notes for the Chapter:**

> I'm soooooooooo sorry about the delay in chapters... heh...  
> long story short, I got distracted from Undertale by Below Zero and Portal (Thanks a lot friends for showing me them...) and then rediscovered my love for Marvel by being invited by a group of friends to see Captain Marvel. Twice.
> 
> Anyway, hopefully i wont get distracted and can write this. Without forgetting to post it. Heh...

Toriel was In the kitchen as usual. She was washing up what Papyrus and Undyne made a mess of the night before. There was a quiet pop and a voice behind her said

"Hey Tori"

She jumped and dropped the plate she was cleaning into the water, the splash wetting her dress.

"Sans! please stop doing that..."

"Sorry"

Sans wandered over to the table and sat down. "I saw Alphys"

"Oh? and what did she want?" Toriel sat down opposite him, curious.

 

He pulled out the copy of the symbols the Doc gave him and showed it to Toriel.

"You know Mettaton, well he had a message feature thingy that Alph didn't give him. This is what he picked up"

Tori looked at the symbols with a confused look on her face.

"Those symbols, they look... familiar"

She had a glazed look in her eyes, as if she was remembering something from the past.

 

The war

 

Protecting... someone

 

She couldn't remember.

 

"Tori... You ok?" Sans put a reassuring hand on hers.

"I'm... fine"

Sans had been born after the war, so Tori found it hard to talk to him about it.

"I need to talk to Asgore about something later on... Could you maybe look after Frisk for me?" Tori asked, hoping he could.

"Heh, I actually wanted to ask if I could take the kiddo to the Librarby. I could do both at once now"

"Good idea. The symbols remind me of the war... I would like to ask Asgore if he knows anything. Oh, and maybe get some more tea"

"Ah, Got it. I'm still curious about what happened, but I'll wait till your ready to talk"

"Thank you Sans"

 

Toriel stood up and went back to washing the dishes, trying to remember where she'd seen the symbols before. She glanced around when she heard Sans move, but he just went through to the living room. Tori continued with her job for a while before being interrupted by a knock on the door.

Toriel wasn't expecting anyone today, but maybe Frisk had invited one of their friends around without telling her.

Again.

She dried her hands and walked towards the door, reaching out to open it, but stopping when she felt the tingle of blue magic wrap its self around her hand.

"Tori, don't..."

"Sans, what is it?"

"There is a human outside... with a red soul..."

Sans and Toriel look at each other, both of them slightly confused.


End file.
